Add mergeDeep method to State type

src/merge.js

@@ -8,20 +8,32 @@ const Props = require('./props')
 
 const internals = {}
 
-exports.create = function(identity, factory) {
+exports.create = function(identity, factory, schema={}) {
 	return {
-		merge: internals.merge.bind(_assign({}, identity, factory))
+		merge: internals.merge.bind(_assign({}, identity, factory)),
+		mergeDeep: internals.mergeDeep.bind(_assign({}, identity, factory, schema))
 	}
 }
 
 internals.merge = function(state, data) {
 	Invariant(this.instanceOf(state), `Instance of ${this.typeName()} is required to merge it with new attributes`)
 	Invariant(Immutable.Iterable.isIterable(data) || _isPlainObject(data), 'Plain object or Immutable Iterable required as source to merge with the state instance')
 
+	return state.merge(internals.mergableInstance.call(this, data));
+}
+
+internals.mergeDeep = function(state, data) {
+	Invariant(this.instanceOf(state), `Instance of ${this.typeName()} is required to merge deep it with new attributes`)
+	Invariant(Immutable.Iterable.isIterable(data) || _isPlainObject(data), 'Plain object or Immutable Iterable required as source to merge deep with the state instance')
+
+	return state.mergeDeep(internals.mergableInstance.call(this, data));
+}
+
+internals.mergableInstance = function(data) {
 	if (!this.instanceOf(data)) {
 		let dataKeys = Immutable.Seq(Immutable.Iterable.isIterable(data) ? data.keys() : _keys(data))
 		data = this.factory(data).filter((val, key) => dataKeys.includes(key))
 	}
 
-	return state.merge(data.remove(Props.cid).remove(Props.name));
+	return data.remove(Props.cid).remove(Props.name)
 }

test/state.js

@@ -328,3 +328,61 @@ Test('state.merge', function(t) {
 		t.ok(TestState.instanceOf(mergedInstance), 'returns an updated instance of the type of the base')
 	}, 'accepts a base and source instance with a different state type')
 })
+
+Test('state.mergeDeep', function(t) {
+	t.plan(3 + 4 + 2 + 2)
+
+	const rawDefaults = {
+		c: 1
+	}
+
+	const TestState = State.create('test-state', rawDefaults)
+	const OtherState = State.create('other-state', rawDefaults)
+
+	const baseInstance = TestState.factory({
+		a: 1,
+		c: 3,
+		d: {
+			e: 5
+		}
+	})
+
+	const rawSource = {
+		a: 2,
+		b: 3,
+		d: {
+			f: 6
+		}
+	}
+
+	const sourceInstance = TestState.factory(rawSource)
+	const otherInstance = OtherState.factory(rawSource)
+
+	t.doesNotThrow(function() {
+		const mergedInstance = TestState.mergeDeep(baseInstance, rawSource)
+
+		t.ok(TestState.instanceOf(mergedInstance), 'returns an updated instance')
+		t.ok(mergedInstance.equals(baseInstance.mergeDeep(rawSource)), 'updated instance has attributes of source deep merged into instance')
+	}, 'accepts a State instance and a plain object of new attributes')
+
+	t.doesNotThrow(function() {
+		const mergedInstance = TestState.mergeDeep(baseInstance, sourceInstance)
+
+		t.ok(TestState.instanceOf(mergedInstance), 'returns an updated instance')
+		t.ok(mergedInstance.equals(baseInstance.mergeDeep(rawDefaults, rawSource)), 'updated instance has attributes of source deep merged into base')
+		t.equals(mergedInstance.get('__cid'), baseInstance.get('__cid'), 'updated instance has client identifer `__cid` from base')
+	}, 'accepts two State instances, a base and source')
+
+	t.doesNotThrow(function() {
+		const withContext = TestState.mergeDeep(baseInstance, sourceInstance)
+		const withoutContext = TestState.mergeDeep.call(null, baseInstance, sourceInstance)
+
+		t.ok(withContext.equals(withoutContext), 'returns the same when called out of context')
+	}, 'can be called without context')
+
+	t.doesNotThrow(function() {
+		const mergedInstance = TestState.mergeDeep(baseInstance, otherInstance)
+
+		t.ok(TestState.instanceOf(mergedInstance), 'returns an updated instance of the type of the base')
+	}, 'accepts a base and source instance with a different state type')
+})